The world has recognized the critical need to decouple economic growth from resource impact. In particular, Europe is aimed at increasing industrial competitiveness whilst drastically reducing resource and energy inefficiencies. The underlying principle is to develop enabling technologies and solutions along the value chain to “do more with less”.
The following objectives have been proposed:                1. A reduction in fossil-fuel energy intensity of up to 30% from current levels by 2030 through a combination of, for example cogeneration-heat-power, process intensification, introduction of novel energy-saving processes, and progressive introduction of renewable energy sources within the process cycle.        2. By 2030, up to 20% reduction in non-renewable, primary raw material intensity versus current levels, by increasing chemical and physical transformation yields and/or using secondary and renewable raw materials with proven sustainability advantages.        
The traditional manufacture of biodiesel is an area where these principles are most relevant since biodiesel, along with bioethanol, is currently the major biofuel in the market and, in addition, its manufacture is resource inefficient because not all the oil feedstock is converted into biofuel.
The industrial method for biodiesel production currently involves the transesterification of triglycerides with excess methanol in the presence of a catalyst to yield fatty acid methyl esters (the desired fuel product) and glycerol (a byproduct without fuel properties).
The resource inefficiency in a synthesis process is quantified by the atom economy, a well known factor that measures the percentage of atomic mass of starting materials that is incorporated into the desired final product of a chemical reaction, fatty acid methyl esters in this case. The atom economy of biodiesel production is 90% which is an unacceptable value for a large-volume commodity.
On the other hand, obtaining glycerol is a problem since there is a huge uncertainty of a secondary market for large volumes of crude glycerol derived from biodiesel manufacture.
The low atom economy combined with the glycerol market uncertainty contribute significantly to decrease the profitability of a biodiesel manufacturing plant.
U.S. Pat. No. 6,890,364 B2 and US 2004/0025417 A1 to Delfort et al. disclose a process for producing glycerol acetals to be used in diesel fuels. The acetal oxygenate additive is claimed to reduce particulate emissions from diesel engines.
U.S. Pat. No. 5,917,059 to Bruchmann as well as U.S. Pat. Nos. 6,713,640 and 6,548,681 to Miller et al. describe a process for preparing acetals.
EP2476740 (A1) relates to a process for the preparation of a mixture comprising fatty acid alkyl esters and acetals with fuel characteristics. The reaction takes place in a closed vessel and comprises reacting a mixture, obtained from the partial transesterification of a triglyceride with a lower alkanol, comprising glycerol, monoglycerides, diglycerides, triglycerides, fatty acid alkyl esters, and excess alkanol with an aldehyde, ketone or diether as a glycerol acetal forming agent in the presence of a solid acid catalyst to form a mixture of the fatty acid alkyl ester and the acetal of the glycerol to provide the composition.
However, none of these documents provides a process for obtaining simultaneously several compositions comprising fatty acid alkyl esters (biodiesel), glycerol formal and the bioester of fatty acid glycerol formal ester, starting from natural oils (triglycerides). The importance for obtaining glycerol formal resides in two facts: the first is that glycerol formal is the lowest possible molecular weight acetal that can be prepared from glycerol; the second is that glycerol formal is the starting material for the preparation of fatty acid glycerol formal esters, a glycerol-containing bioester with fuel characteristics similar to biodiesel. The possibility for obtaining the lowest possible molecular weight glycerol acetal (glycerol formal) is extremely relevant for the fuel properties of the fuel compositions that can be prepared from these components as already disclosed in EP 2049623.
It is therefore an object of the present invention to provide a flexible synthetic process that transforms efficiently triglycerides and glycerol into a variety of fuels whose actual compositions depend on the specific selection of raw materials and reaction conditions.
It is a further object of the present invention to provide a range of compositions useful as bio fuels in both automotive and industrial applications (e.g. in industrial boilers).